package com.siro.gulimall.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.siro.common.to.es.SkuEsModel;
import com.siro.common.utils.R;
import com.siro.gulimall.search.config.ElasticSearchConfig;
import com.siro.gulimall.search.constant.EsConstant;
import com.siro.gulimall.search.feign.ProductFeignService;
import com.siro.gulimall.search.service.MallSearchService;
import com.siro.gulimall.search.vo.AttrResponseVo;
import com.siro.gulimall.search.vo.BrandResponseVo;
import com.siro.gulimall.search.vo.SearchParam;
import com.siro.gulimall.search.vo.SearchResult;
import org.apache.commons.lang.StringUtils;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.*;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.Aggregation;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @author Starsea
 * @date 2022-04-11 20:54
 */
@Service
public class MallSearchServiceImpl implements MallSearchService {

    @Autowired
    private RestHighLevelClient client;

    @Autowired
    private ProductFeignService productFeignService;

    /**
     * 根据传递过来的页面查询参数，去es中检索商品
     * @param param 检索所有参数
     * @return 返回检索的所有结果
     */
    @Override
    public SearchResult search(SearchParam param) {
        // 动态构建出查询需要DSL语句
        SearchResult result = null;

        // 1.准备检索请求
        SearchRequest searchRequest = buildSearchRequest(param);

        try {
            //2.执行检索请求
            SearchResponse response = client.search(searchRequest, ElasticSearchConfig.COMMON_OPTIONS);

            //3.分析响应数据封装我们需要的格式
            result = buildSearchResponse(response, param);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 准备检索请求
     * 模糊匹配、过滤（按照属性，分类，品牌，价格区间，库存）、排序、分页、高亮、聚合分析
     * @return
     */
    private SearchRequest buildSearchRequest(SearchParam param) {
        //构建DSL语句
        SearchSourceBuilder searchBuilder = new SearchSourceBuilder();

        /**
         * 查询：模糊匹配、过滤（分类，品牌，按照属性，库存，价格区间）
         */
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
        //1. must-模糊匹配
        if (!StringUtils.isEmpty(param.getKeyword())) {
            boolQuery.must(QueryBuilders.matchQuery("skuTitle",param.getKeyword()));
        }

        //1.2 filter - 按照三级分类id查询
        if (param.getCatalog3Id() != null) {
            boolQuery.filter(QueryBuilders.termQuery("catalogId",param.getCatalog3Id()));
        }

        //1.2 filter - 按照品牌id查询
        if (param.getBrandId() != null && param.getBrandId().size() > 0) {
            boolQuery.filter(QueryBuilders.termsQuery("brandId",param.getBrandId()));
        }

        //1.2 filter - 按照所有指定属性查询
        if (param.getAttrs() != null && param.getAttrs().size() > 0) {
            //attrs=1_3G:4G&attrs=2_5寸:8寸
            for (String attrStr : param.getAttrs()) {
                BoolQueryBuilder nestBoolQuery = QueryBuilders.boolQuery();
                //attrs=1_3G:4G
                String[] s = attrStr.split("_");
                String attrId = s[0];//检索的属性id
                String[] attrValue = s[1].split(":");//这个属性检索用的值
                nestBoolQuery.must(QueryBuilders.termQuery("attrs.attrId",attrId));
                nestBoolQuery.must(QueryBuilders.termsQuery("attrs.attrValue",attrValue));
                NestedQueryBuilder nestedQuery = QueryBuilders.nestedQuery("attrs", nestBoolQuery, ScoreMode.None);
                boolQuery.filter(nestedQuery);
            }
        }

        //1.2 filter - 按照库存查询
        if (param.getHasStock() != null) {
            boolQuery.filter(QueryBuilders.termQuery("hasStock",param.getHasStock() == 1));
        }

        //1.2 filter - 按照价格区间查询
        if (!StringUtils.isEmpty(param.getSkuPrice())) {
            // 1_500/_500/500_
            RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("skuPrice");
            String[] s = param.getSkuPrice().split("_");
            if (s.length == 2) {
                //区间
                rangeQuery.gte(s[0]).lte(s[1]);
            } else if (s.length == 1) {
                if (param.getSkuPrice().startsWith("_")) {
                    //_500
                    rangeQuery.lte(s[0]);
                }
                if (param.getSkuPrice().endsWith("_")) {
                    //_500
                    rangeQuery.gte(s[0]);
                }
            }
            boolQuery.filter(rangeQuery);
        }
        //把之前所有的查询条件进行封装
        searchBuilder.query(boolQuery);

        /**
         * 排序、分页、高亮
         */
        //2.1 排序
        if (!StringUtils.isEmpty(param.getSort())) {
            //sort=hotScore_asc/desc
            String sort = param.getSort();
            String[] s = sort.split("_");
            SortOrder order = s[1].equalsIgnoreCase("asc") ? SortOrder.ASC : SortOrder.DESC;
            searchBuilder.sort(s[0], order);
        }

        //2.2 分页
        // pageNum:1    from:1  size:5  [0,1,2,3,4]
        // pageNum:2    from:5  size:5
        // from = (pageNum-1)*size
        searchBuilder.from((param.getPageNum()-1)*EsConstant.PRODUCT_PAGESIZE);//从哪里开始
        searchBuilder.size(EsConstant.PRODUCT_PAGESIZE);//有多条数据

        //2.3 高亮
        if (!StringUtils.isEmpty(param.getKeyword())) {
            HighlightBuilder builder = new HighlightBuilder();
            builder.field("skuTitle");
            builder.preTags("<b style='color:red'>");
            builder.postTags("</b>");
            searchBuilder.highlighter(builder);
        }

        /**
         * 聚合分析
         */
        //1. 品牌聚合
        TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg");
        brand_agg.field("brandId").size(50);
        // 品牌聚合的子聚合
        brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg").field("brandName").size(1));
        brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg").field("brandImg").size(1));
        searchBuilder.aggregation(brand_agg);

        //2. 分类聚合
        TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg");
        catalog_agg.field("catalogId").size(20);
        catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));
        searchBuilder.aggregation(catalog_agg);

        //3. 属性聚合
        NestedAggregationBuilder attr_agg = AggregationBuilders.nested("attr_agg", "attrs");
        //聚合出当前所有的attrId
        TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId");
        //聚合分析出当前attrId对应的名字attrName
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
        //聚合分析出当前attrId对应的所有可能的属性值attrValue
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attrs.attrValue").size(50));
        attr_agg.subAggregation(attr_id_agg);
        searchBuilder.aggregation(attr_agg);

        String s = searchBuilder.toString();
        System.out.println("构建的DSL语句 = " + s);

        SearchRequest searchRequest = new SearchRequest(new String[]{EsConstant.PRODUCT_INDEX}, searchBuilder);
        return searchRequest;
    }

    /**
     * 构建结果数据
     * @param response
     * @return
     */
    private SearchResult buildSearchResponse(SearchResponse response, SearchParam param) {
        //TODO 通过debugger断点来写
        SearchResult result = new SearchResult();
        //1. 从hits结果中 - 返回查询到的所有商品
        SearchHits hits = response.getHits();
        List<SkuEsModel> esModels = new ArrayList<>();
        if (hits.getHits()!= null && hits.getHits().length > 0) {
            for (SearchHit hit : hits.getHits()) {
                String sourceAsString = hit.getSourceAsString();
                SkuEsModel esModel = JSON.parseObject(sourceAsString, SkuEsModel.class);
                //设置高亮字段
                if (!StringUtils.isEmpty(param.getKeyword())) {
                    HighlightField skuTitle = hit.getHighlightFields().get("skuTitle");
                    String string = skuTitle.getFragments()[0].string();
                    esModel.setSkuTitle(string);
                }
                esModels.add(esModel);
            }
        }
        result.setProducts(esModels);

        //2. 从聚合结果中 - 返回当前所有商品涉及到的所有分类信息
        ParsedLongTerms catalog_agg = response.getAggregations().get("catalog_agg");//通过断点查询返回类型

        List<SearchResult.CatalogVo> catalogVos = new ArrayList<>();
        List<? extends Terms.Bucket> buckets = catalog_agg.getBuckets();
        for (Terms.Bucket bucket : buckets) {
            SearchResult.CatalogVo catalogVo = new SearchResult.CatalogVo();
            //分类id
            String keyAsString = bucket.getKeyAsString();
            catalogVo.setCatalogId(Long.parseLong(keyAsString));
            //分类名字
            ParsedStringTerms catalog_name_agg = bucket.getAggregations().get("catalog_name_agg");
            String catelog_name = catalog_name_agg.getBuckets().get(0).getKeyAsString();
            catalogVo.setCatalogName(catelog_name);

            catalogVos.add(catalogVo);
        }
        result.setCatalogs(catalogVos);

        //3. 从聚合结果中 - 返回当前所有商品涉及到的所有品牌信息
        ParsedLongTerms brand_agg = response.getAggregations().get("brand_agg");//通过断点查询返回类型

        List<SearchResult.BrandVo> brandVos = new ArrayList<>();
        for (Terms.Bucket bucket : brand_agg.getBuckets()) {
            SearchResult.BrandVo brandVo = new SearchResult.BrandVo();
            //品牌id
            long brandId = bucket.getKeyAsNumber().longValue();
            brandVo.setBrandId(brandId);
            //品牌名字
            ParsedStringTerms brand_name_agg = bucket.getAggregations().get("brand_name_agg");
            String brandName = brand_name_agg.getBuckets().get(0).getKeyAsString();
            brandVo.setBrandName(brandName);
            //品牌图片
            ParsedStringTerms brand_img_agg = bucket.getAggregations().get("brand_img_agg");
            String brandImg = brand_img_agg.getBuckets().get(0).getKeyAsString();
            brandVo.setBrandImg(brandImg);

            brandVos.add(brandVo);
        }
        result.setBrands(brandVos);

        //4. 从聚合结果中 - 返回当前所有商品涉及到的所有属性信息
        ParsedNested attr_agg = response.getAggregations().get("attr_agg");

        List<SearchResult.AttrVo> attrVos = new ArrayList<>();
        ParsedLongTerms attr_id_agg = attr_agg.getAggregations().get("attr_id_agg");
        for (Terms.Bucket bucket : attr_id_agg.getBuckets()) {
            SearchResult.AttrVo attrVo = new SearchResult.AttrVo();
            // 属性id
            long attrId = bucket.getKeyAsNumber().longValue();
            attrVo.setAttrId(attrId);
            //属性名字
            ParsedStringTerms attr_name_agg = bucket.getAggregations().get("attr_name_agg");
            String attrName = attr_name_agg.getBuckets().get(0).getKeyAsString();
            attrVo.setAttrName(attrName);
            //属性的值
            List<String> attrValues = ((ParsedStringTerms) bucket.getAggregations().get("attr_value_agg")).getBuckets().stream().map(item -> {
                String keyAsString = item.getKeyAsString();
                return keyAsString;
            }).collect(Collectors.toList());
            attrVo.setAttrValue(attrValues);

            attrVos.add(attrVo);
        }
        result.setAttrs(attrVos);

        //5. 分页信息 - 页码
        result.setPageNum(param.getPageNum());

        //6. 分页信息 - 总记录数
        long total = hits.getTotalHits().value;
        result.setTotal(total);

        //7. 分页信息 - 总页码
        int totalPages = (int)total % EsConstant.PRODUCT_PAGESIZE == 0 ? (int)total / EsConstant.PRODUCT_PAGESIZE : ((int)total / EsConstant.PRODUCT_PAGESIZE + 1);
        result.setTotalPages(totalPages);

        //可遍历的导航页（为了前端方便）
        List<Integer> pageNavs = new ArrayList<>();
        for (int i = 1; i <= totalPages; i++) {
            pageNavs.add(i);
        }
        result.setPageNavs(pageNavs);

        //构建面包屑导航数据
        if (param.getAttrs() != null && param.getAttrs().size() > 0) {
            List<SearchResult.NavVo> collect = param.getAttrs().stream().map(attr -> {
                //分析每个attrs传过来的查询参数值
                SearchResult.NavVo navVo = new SearchResult.NavVo();
                // attrs=2_5寸:6寸
                String[] s = attr.split("_");
                navVo.setNavValue(s[1]);

                R r = productFeignService.attrInfo(Long.parseLong(s[0]));
                result.getAttrIds().add(Long.parseLong(s[0]));
                if (r.getCode() == 0) {
                    AttrResponseVo data = r.getData("attr", new TypeReference<AttrResponseVo>() {
                    });
                    navVo.setNavName(data.getAttrName());
                } else {
                    navVo.setNavName(s[0]);
                }

                //取消了这个面包屑以后，我们要跳转到那个地方
                //将请求地址的url里面的当前置空
                String replace = replaceQueryString(param, attr,"attrs");
                navVo.setLink("http://search.gulimall.com/list.html?" + replace);
                return navVo;
            }).collect(Collectors.toList());
            result.setNavs(collect);
        }

        //条件筛选联动，品牌
        if (param.getBrandId() != null && param.getBrandId().size() > 0) {
            List<SearchResult.NavVo> navs = result.getNavs();
            SearchResult.NavVo navVo = new SearchResult.NavVo();
            navVo.setNavName("品牌");

            R r = productFeignService.brandInfo(param.getBrandId());
            if (r.getCode() == 0) {
                List<BrandResponseVo> brand = r.getData("brand", new TypeReference<List<BrandResponseVo>>() {
                });

                StringBuffer buffer = new StringBuffer();
                String replace = "";
                for (BrandResponseVo brandResponseVo : brand) {
                    buffer.append(brandResponseVo.getName());
                    replace = replaceQueryString(param, brandResponseVo.getBrandId()+"","brandId");
                }
                navVo.setNavValue(buffer.toString());
                navVo.setLink("http://search.gulimall.com/list.html?" + replace);
            }
            navs.add(navVo);
        }

        //TODO 条件筛选联动，分类
        //不需要link属性

        return result;
    }

    /**
     * 字符串替换
     * @param param
     * @param value
     * @param key
     * @return
     */
    private String replaceQueryString(SearchParam param, String value, String key) {
        String encode = null;
        try {
            encode = URLEncoder.encode(value, "UTF-8");
            encode = encode.replace("+","%20");//浏览器对空格编码和Java不一样，需要特殊处理
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        String replace = param.get_queryString().replace("&"+key+"=" + encode, "");
        return replace;
    }
}
